Automatic impact device

ABSTRACT

An impact tool useful for performing a number of different surgical and industrial functions is provided. The invented tool can perform such surgical functions as freeing cement, implanting pins, and setting guides and industrial functions such as installing various fasteners. The tool comprises a body having a quick disconnect assembly coupled to a second end for quickly attaching and detaching different desired surgical and industrial implements to the tool. The quick disconnect assembly communicates with an impact inducing assembly is retained in a channel in the body. The impact inducing assembly causes an implement retained in the quick disconnect assembly to deliver an impact with a calibrated force to a desired object. The orientation of the components of the impact inducing assembly can be inverted so that the tool is actuated to apply an instantaneous extraction force to the desired fastener or surgical aid. In the alternative embodiment the user draws the tool away from an object secured to the quick disconnect assembly until the impact inducing assembly disengages the quick disconnect assembly to impel the implement along the channel for delivering an instantaneous extraction force to the desired object, for at least partially withdrawing a portion of the object from a surface in which the object is imbedded. An antirotation assembly may be provided to determine and maintain a desired orientation of various implements coupled to the quick disconnect assembly, when the implement is obscured from the user&#39;s view.

This application is a continuation-in-part of application Ser. No.08/958,773, filed Oct. 27, 1997, now U.S. Pat. No. 5,827,290, thespecification of which are hereby incorporated by reference in itsentirety, which is a continuation-in-part of application Ser. No.08/735,185, filed Oct. 25, 1996, now U.S. Pat. No. 5,735,855.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to impact devices, and moreparticularly, to an impact tool for performing different surgicalfunctions in various different surgical procedures and for performingvarious different industrial functions.

2. Description of Related Art

As can well be appreciated, the instruments a surgeon uses whileperforming a surgical procedure are of the utmost importance. Ease ofuse, reliability, and operating precision are important features ofthese instruments.

When performing surgical procedures, such as orthopedic procedures, thesurgeon often uses several instruments that each perform a differentfunction during the procedure. In a procedure, such as a hip replacementoperation for example, the surgeon first typically removes the head ofthe femur. Once the head of the femur is removed, the surgeon may use anosteotome for hollowing out the medullary canal of the femur, to form acavity in the bone, to prepare the femur for receiving the replacementfemoral component. Once the cavity is suitably prepared, an appropriatemedical adhesive, such as a liquid acrylic cement, is disposed in thecavity, and the replacement femoral component is disposed in the cavityto affix the component to the femur.

If the purpose of the hip replacement operation is to supplant a failedreplacement, the surgeon may further use a gouge and chisel along withthe osteotome. The gouge and other instruments are used to removeresidual adhesive from the cavity, due to the preceding hip replacement,to prepare the cavity for the new femoral component.

Additionally, these and other instruments are used for a number ofdifferent purposes. For example, another use of chisels is to removebone spurs. Another instrument that is used by orthopedic surgeons is asurgical pin inserter. The pin inserter may be used by the surgeon forinserting surgical pins that facilitate the fixation of fractured bones.The pin inserter is also used to temporarily couple guides to variousbones, such as securing guides to the tibia or femur during a kneereplacement procedure. Also, when a hip replacement operation issupplanting a failed replacement, guides can be employed when affixingthe new femoral component to the femur.

Common to each of these instruments, is that an instantaneous force hasto be applied to the instrument, to cause the instrument to function.The force causes the instrument to deliver an instantaneous impact to adesired object, such as a portion of bone or a pin, for performing thedesired function, such as cutting bone or inserting the pin. Knownmedical methods usually require the surgeon to strike the instrumentwith an appropriate device, such as a hammer, to cause the instrument tomomentarily impact the object.

As can be appreciated, it is substantially difficult to manually strikethe instrument with a consistent, optimal impact force, which can resultin either an excessive or insufficient impact force being applied to theobject by the instrument. To inhibit an excessive force from beingapplied to the object, the surgeon often repeatedly strikes theinstrument with a force that is somewhat less than sufficient, whichoften results in the procedure taking longer than is necessary. Afurther disadvantage of using a hammer to induce an impact, is that thesurgeon must operate both the hammer and instrument. Thus, the surgeonis not afforded one-handed operation of the instrument.

To increase the speed with which the desired implement deliverssuccessive impacts, a pneumatic power source may be coupled to theinstrument. However, a disadvantage of using pneumatic power, is thatthe instrument rapidly and repeatedly impacts the object, causing theinstrument to be somewhat difficult to control.

It therefore would be advantageous to provide a means for enabling aninstrument to deliver an impact to an object with an optimal force andin a controllable manner.

Additionally, during performance of any of the above discussed surgicalprocedures, or any one of several well known procedures, it is oftennecessary to affix and remove surgical aids, such as the surgical pins,that are temporarily secured to a patient's bones for securing guides tothe bones to facilitate performance of the procedure. Also, sometimeafter performing any one of the above discussed surgical procedures, orany one of several well known procedures, it is often necessary toremove surgical aids, such as the surgical pins, that are temporarilysecured to a patient's bones to facilitate fixation of the fracturedbones.

However, common to installing these surgical aids, it is often difficultto remove these aids and other devices, particularly in a controlled andefficient manner. It therefore would be advantageous to provide a meansfor facilitating removal of these and other devices that are temporarilyaffixed to a patient's bones, or other portions of the patient'sanatomy.

Punch tools are well known in the prior art. Punches are used for anumber of different applications, such as making shallow indentations inmetal work or breaking glass. For example, a center punch can be used tomake a shallow indentation in a portion of sheet metal, to prepare themetal for accurately drilling openings therethrough at predeterminedpositions. Punches are additionally used by emergency personnel to breakvehicle windows and other appropriate purposes.

A center punch tool typically comprises a hollow steel body with a steeltip that extends through an end of the body. The tip is usuallyconfigured with a conical end portion for impacting a desired surface. Aloaded spring is retained in the body, with release means coupling thespring to the tip. The body may have a handle coupled to the spring, toadjust for light or heavy strokes of the tip.

In use, the conical end of the tip is pressed against a surface to beimpacted by the center punch. As the tip is pressed against the surface,the tip is forced into the body. As the tip is pushed into the body,upon reaching a determined point in the body, the release means causesthe spring to instantaneously propel the end of the tip into thesurface, to momentarily impact the surface, thus indenting or breakingthe surface struck by the tip.

A disadvantage of known punch tools is that they are not well suited fora number of different industrial uses. A further disadvantage of knownpunch tools is that they are not configured with means for couplingdifferent implements thereto.

There, therefore, exists a need for an impact tool for performingdifferent surgical and industrial functions that delivers an impact toan object with an optimal force and in a controllable manner and iscapable of applying an instantaneous extraction force to an object toeffect removal of the object from a surface in which at least a portionof the object is imbedded.

OBJECTS OF THE INVENTION

It is therefore an object of the present invention to provide animproved impact tool;

It is another object of the present invention to provide an improvedimpact tool for performing different surgical functions;

It is a further object of the present invention to provide an improvedimpact tool that is well suited for performing a number of differentindustrial functions;

It is still another object of the present invention to provide animproved impact tool that delivers an impact to an object with anoptimal force and in a controllable manner;

It is a further object of the present invention to provide an improvedimpact tool that is coupleable to different objects and is actuated forinstantaneous extraction of the objects from a surface in which at leasta portion of the object is imbedded;

It is yet a further object of the present invention to provide animproved impact tool that affords one-handed operation thereof; and

It is another object of the present invention to provide an impact toolthat includes a quick disconnect fitting for alternately quicklyconnecting and disconnecting a number of different implements thereto.

SUMMARY OF THE INVENTION

These and other objects and advantages of the present invention areachieved by providing an improved impact tool for performing a number ofdifferent surgical and industrial functions. The improved impact tool ofthe present invention is useful for performing a number of differentfunctions in various surgical procedures, such as hip replacementprocedures for example. Several different surgical implements canalternately be coupled to the invented tool during surgical procedures,to perform such surgical functions as freeing and removing cement,inserting pins, accurately setting guides, and implanting surgicalstaples. Some of these surgical implements include an acetabularadjuster, a surgical pin inserter, a surgical stapler, a bone chisel, anosteotome, and a gouge.

Additionally, the improved impact tool of the present invention may beutilized in different industrial applications wherever an impact forceis desired, such as the several different impact forces associated withconstruction, for instance. The impact tool of the present invention canbe configured into several different dimensions that render the toolsuitable for delivering an impact of sufficient force to variousfasteners, such as nails or other similar fasteners, to drive thefastener into a surface comprising wood, sheetrock or drywall, or metalalloy surfaces among others.

Further, the tool of the present invention includes means for effectingremoval of various surgical aids and other devices, along with variousindustrial fasteners. As with installing surgical aids and industrialfasteners, along with other devices, it is often difficult to removethese devices, particularly in a controlled and efficient manner. Theimpact tool of the present invention is capable of applying aninstantaneous extraction force to an object to effect removal of theobject from a surface in which at least a portion of the object isimbedded.

For example, the invented impact tool is coupleable to differentimplements adapted to be secured to a surgical aid, such as a pin. Theinvented tool then is actuated for applying an instantaneous extractionforce to the pin, to effect removal of the pin from a bone in which atleast a portion of the pin is imbedded. The tool can be repeatedlyactuated until the pin is entirely removed from the bone. Similarly, theinvented impact tool can be secured to industrial fasteners for removingthe fasteners from a surface that the fasteners are imbedded.

In the preferred embodiment of the present invention, the improvedimpact tool comprises a handle portion or body having an impact forcecalibrating means coupled to a first end thereof and a quick disconnectassembly secured in a second end. The quick disconnect assemblycomprises a chuck having a rod that extends into a channel in the body,for coupling the quick disconnect assembly to the body, and a jawassembly. The jaw assembly includes a quick-release means for quicklyattaching and detaching different desired surgical and industrialimplements to the tool.

The channel extends through the body and has a first region that extendsfrom the first end of the body to a midpoint that is intermediate thefirst and second ends of the body, and a second region that extends fromthe second end to the midpoint. The channel further includes atransition region that extends about its midpoint.

An impact inducing assembly is provided for causing an implement coupledto the quick disconnect assembly to deliver an impact to a desiredobject, such as the above discussed surgical aids and industrialfasteners, with an impact force calibrated by the calibrating means, andwithout the use of external means, such as a hammer. The impact inducingassembly is retained in the channel and comprises a piston slidablyretained in the first region of the channel, a main spring interposedbetween the piston and calibrating means, and coupled thereto, and anactuation mechanism configured to releasably engage the rod.

In the preferred embodiment, the actuation mechanism comprises anactuation spring secured in an inner surface of the piston and a triggermember slidably retained in a hole through a wall thereof and coupled tothe actuation spring. The trigger has an opening disposed therethroughthat is dimensioned to allow the rod to extend through the trigger andinto the piston. The actuation spring biases the trigger outwardly, sothat the trigger projects outwardly from the piston to contact thetransition region of the channel.

Optionally, a trigger means may be disposed through the body and coupledthereto, for contacting the actuation mechanism. The trigger means maybe positioned on the body, between the second end and midpoint,depending upon such factors as the intended application of the inventedtool, for example. The trigger means enables the implement to deliver animpact, without the user having to exert substantial pressure on theobject, to initiate the impact. Thus, the trigger means enables the toolto be used in applications where only a slight impact force is desired,such as dentistry.

An antirotation assembly may be provided to prevent the implement fromrotating relative to the body, while the rod travels along the channel.Preferably, the antirotation assembly includes an adjustable membersecured in the second region of the channel. The adjustable member hasan aperture disposed therethrough configured complementary to the endsection and a mid section of the rod, for allowing the rod to passtherethrough, while preventing the rod from rotating about in thechannel. Additionally, a depression may be formed in the periphery ofthe body, preferably proximal to the second end thereof. Theantirotation assembly and depression coact to enable a user to determineand maintain a desired orientation of various implements coupled to thequick disconnect assembly, when the implement is obscured from theuser's view.

Return means are provided for causing the rod to be engaged by theactuation mechanism for returning the impact inducing assembly to aninitial position, thus affording one-handed operation of the inventedtool. In the preferred embodiment, the return means comprises a returnspring interposed between the adjustable member and the second end ofthe body and coupled to the rod of the quick disconnect assembly'schuck. The return spring biases the rod toward the second end of thebody, causing the end of the rod to be engaged by the trigger, thuscoupling the rod to the piston.

In use, the impact inducing means is in the initial position, whereinthe main spring exerts force on the piston to retain the actuationmechanism in the second region of the channel, to prevent the impactinducing means from causing the implement to deliver an impact. Aconnecting portion of a selected surgical or industrial implement iscoupled to the quick disconnect assembly. The user grasps the tool andmay place their thumb, or one of their other fingers, for maintainingthe orientation of the implement if necessary. As the user appliespressure to the implement with the tool, the piston is urged toward thefirst end of the body to compress the main spring. The piston is urgedtoward the first end until a head of the trigger contacts the transitionregion of the channel.

As the head of the trigger contacts the transition region, the triggeris pushed into the hole for compressing the actuation spring, todisengage an end section of the chuck's rod from the trigger for causingthe inducing means to deliver an impact to the desired object. Theimplement is caused to deliver an impact, due to the rod passing intothe piston, which causes the main spring to propel the piston along therod until the piston strikes a shoulder thereof. Once the piston strikesthe shoulder, the piston and rod are propelled instantaneously along thesecond region of the channel until the implement impacts the object. Asthe rod is propelled along the second region, the antirotation assemblyprevents the rod from rotating about in the channel, thus affordingone-handed operation of the invention.

After the implement impacts the object, the piston is drawn toward thefirst end of the body by the calibration means with the return meansretaining the rod proximal to the second end, for withdrawing the rodout of the cavity. The rod is drawn out of the piston until a portion ofthe end section passes into the opening in the trigger. The actuationspring biases the trigger outwardly, such that the bottom edge of thetrigger is pressed against the end section to engage the rod and returnthe impact inducing means to the initial position. This enables the toolof the present invention to cause the implement to deliver subsequentimpacts to the object with a consistent and optimal impact forcecontrolled by the calibration means.

Alternatively, the orientation of the components of the impact inducingassembly, along with the orientation of the transition region of thechannel, can essentially be inverted so that invented tool can beactuated to apply an instantaneous extraction force to the desiredfastener or surgical aid. In the alternative embodiment, an implementcoupled to the quick disconnect assembly is provided with means forsecurely attaching the implement to the object, such as the abovediscussed surgical aids and industrial fasteners. The user then drawsthe impact tool away from the object until the trigger of the impactinducing assembly contacts the transition region and disengages the endsection of the chuck's rod to cause the impact inducing means to impelthe implement along the channel for delivering an instantaneousextraction force to the desired object, for at least partiallywithdrawing a portion of the object from a surface in which the objectis imbedded. The user can repeatedly draw the impact tool away from theobject until the object is completely removed from the surface ifdesired.

BRIEF DESCRIPTION OF THE DRAWINGS

The objects and features of the present invention, which are believed tobe novel, are set forth with particularity in the appended claims. Thepresent invention, both as to its organization and manner of operation,together with further objects and advantages, may best be understood byreference to the following description, taken in connection with theaccompanying drawings, in which:

FIG. 1 is a perspective view showing a preferred embodiment of an impacttool for use in surgical procedures of the present invention with asurgical implement coupled thereto;

FIG. 2 is a perspective, exploded view showing the preferred embodimentof the present invention;

FIG. 3 is a cross-sectional view of the preferred embodiment showingcomponents thereof;

FIG. 4 is a cross-sectional view of the preferred embodiment showingcomponents thereof in an initial position; and

FIGS. 5A and 5B are a cross-sectional views of a chuck assembly of thepreferred embodiment of the present invention.

FIGS. 6 is a cross-sectional view of an extraction embodiment of thepresent invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The following description is provided to enable any person skilled inthe art to make and use the invention and sets forth the best modespresently contemplated by the inventor of carrying out the invention.Various modifications, however, will remain readily apparent to thoseskilled in the art, since the generic principles of the presentinvention have been defined herein.

Referring now to FIG. 1 and FIG. 2 of the drawings, there is showngenerally at 10, a preferred embodiment of an impact tool for use in anumber of different surgical and industrial functions, constructedaccording to the principles of the present invention. The tool 10 ispreferably fabricated from known light, strong, and rigid biocompatiblemetal alloys, or polymeric composites, or other known suitablematerials. In the present invention, the invented tool 10 is preferablyfabricated from suitable metal alloys, such as a stainless steel alloysold under the trade name Stellite, and titanium alloys. The inventedtool 10 may also be fabricated from cobalt alloys sold under the tradenames Elgiloy and Carpenter MP35.

The impact tool 10 of the present invention is useful for performing anumber of different functions in various surgical procedures, such aship replacement procedures. Several different surgical implements canalternately be coupled to the invented tool during surgical procedures,to perform such surgical functions as freeing and removing cement,inserting pins, accurately setting guides, and implanting surgicalstaples. Some of these surgical implements include an acetabularadjuster, a surgical pin inserter, a surgical stapler, a bone chisel, anosteotome, and a gouge.

Additionally, the impact tool 10 may be utilized in different industrialapplications wherever an impact force is desired, such as the severaldifferent impact forces associated with construction, for instance. Thetool 10 can be configured into several different dimensions that renderthe tool 10 suitable for delivering an impact of sufficient force tovarious fasteners, such as nails or other similar fasteners, to drivethe fastener into a surface comprising wood, sheetrock or drywall, ormetal alloy surfaces, among others.

Further, the tool 10 of the present invention includes means foreffecting removal of various surgical aids and other devices, along withvarious industrial fasteners. As with installing surgical aids andindustrial fasteners, along with other devices, it is often difficult toremove these devices, particularly in a controlled and efficient manner.The impact tool 10 of the present invention is capable of applying aninstantaneous extraction force to an object to effect removal of theobject from a surface in which at least a portion of the object isimbedded. For example, the invented impact tool 10 is coupleable todifferent implements adapted to be secured to a surgical aid, such as apin. The tool 10 then is actuated for applying an instantaneousextraction force to the pin, to effect removal of the pin from a bone inwhich at east a portion of the pin is imbedded. The tool 10 can berepeatedly actuated until the pin is entirely removed from the bone. Ina similar fashion, the invented impact tool 10 can be secured toindustrial fasteners for removing the fasteners from a surface that thefasteners are imbedded.

Referring still to FIG. 1 and FIG. 2, the invented tool 10 comprises ahandle portion or body 12 having an impact force calibrating means 13coupled to a first end 16 thereof and a quick disconnect assembly 18secured in a second end 20. The body 12 optionally may be provided withan ovular depression 19 formed in the periphery thereof, preferablyproximal to the second end 20. The depression 19 is provided forplacement of the user's thumb to enhance grasping of the body 12, forpreventing the tool 10 from inadvertently moving in a user's hand whilethe tool 10 is in use. Additionally, the depression 19 enables a user todetermine and maintain a desired orientation of various implementscoupled to the quick disconnect assembly 18, when the implement isobscured from the user's view.

Referring now to FIGS. 1-4, in the preferred embodiment of the inventedtool 10, the body 12 is elongated and has a channel 24 that extendstherethrough and parallel to a longitudinal axis L of the body 12. Inthe preferred embodiment, the channel 24 has a first region 26 of afirst diameter extending from the first end 16 to a midpoint 28 that isintermediate the first and second ends 16, 20, a second region 30 havinga diameter greater than the first region 26 extending from the secondend 20 to the midpoint 28, and a conical ramp 32 formed about themidpoint 28. The conical ramp 32 provides a smooth transition regionbetween the first and second regions 26, 30 of the channel 24. Further,a portion 34 of the first region 26 of the channel 24 may be threadedfor receiving the calibrating means 13, and a portion 36 of the secondregion 30 of the channel 24 may be threaded for coupling the quickdisconnect assembly 18 to the body 12.

The calibrating means 13 preferably comprises a conical knob 14 having ascrew 38 made integral therewith. The screw 38 is configured to matewith the threaded portion 34 of the channel's first region 26 foradjustably coupling the knob 14 to the body 12. The knob 14 may beprovided with a multiplicity of spatially positioned elongated furrows40 formed in the periphery thereof. The furrows 40 are provided toenhance gripping of the knob 14, when adjusting the knob 14 to calibrateand adjust the impact force to be delivered by the tool 10.

Referring now to FIGS. 2-4 of the drawing figures, the preferredembodiment of the invented tool 10 includes an impact inducing assembly,shown generally at 41, retained in the channel 24. The impact inducingassembly 41 is provided to cause a surgical implement 42 retained in thequick disconnect assembly 18 to deliver an impact to a desired object,with an impact force calibrated by the calibrating means 13. In thepreferred embodiment, the impact inducing assembly 41 comprises a hollowpiston 44 slidably retained in the channel 24. The piston 44 has a head46 formed on a first end 48, and an elongated cavity 50 disposed througha second end 52 thereof. The head 46 of the piston 44 has a diameterless than the piston 44, to form a flange 54 about the first end 48. Ahole 56 is formed through a wall 58 of the piston 44 proximal to thesecond end 52. The hole 56 extends perpendicular to the cavity 50 andinto an inner surface 60 thereof, such that a depression 62 is formed inthe inner surface 60 of the piston 44, aligned with the hole 56.

The impact inducing assembly 41 further includes a main spring 64 thatis interposed between the piston 44 and calibrating means 13. The mainspring 64 is configured to frictionally, engage the head 46 of thepiston 44 and to couple to the screw 38 of the knob 14. In use, as theknob 14 is rotated clockwise, the screw 38 extends further into thefirst region 26 of the channel 24 to increasingly bias the main spring64 against the head 46, for increasing the impact force generated by theimpact inducing assembly 41.

Referring now to the drawing figures, the quick disconnect assembly 18includes a chuck 21 having a rod 66 configured to extend into thechannel 24, for coupling the quick disconnect assembly 18 to the body12. As shown in FIGS. 2-4, the rod 66 has an end section 68 that extendsfrom an end 70 thereof to a mid section 72. The end section 68 isdimensioned to extend into the cavity 50, with the mid section 72 havinga diameter greater than the diameter of the end section 68, for forminga shoulder 74 about the juncture of the end and mid sections 68, 72.

Preferably, each of the end and mid sections 68, 72 are substantiallycylindrical with chordal sides to prevent the rod 66 from rotating aboutthe longitudinal axis L of the body, when the rod 66 is traveling alongthe second region 30 of the channel 24 (discussed hereafter).Additionally, a boss 71 is formed on the end 70 of the rod 66 to form aflange 73.

Referring now to FIG. 2 and FIGS. 5A-5B, the quick disconnect assembly18 is provided with a quick-release jaw means 22 for quickly attachingand detaching different desired implements, such as the above discussedsurgical and industrial implements, to the tool 10. In the preferredembodiment, the quick-release jaw means 22 is integrally formed with thechuck 21 and diametrically opposed to the rod 66. The jaw means 22includes a cylindrical mouth 76 that provides access to an elongatedopening 78 in the quick disconnect assembly 18. The opening 78 isconfigured to receive a connecting portion 80 of an end region 82 of theimplement 42 for coupling the implement 42 to the assembly 18.

In the present invention, the connecting portion 80 of the implement 42comprises a narrowed portion 84 extending between an anterior shoulder86 and a posterior shoulder 88. An end 91 of the connecting portion 80may be configured with chamfered edges 93 so that the implement 42 canbe coupled to the quick disconnect assembly 18 without having to depressa push-button 92 thereof (discussed hereinafter).

While the only implement 42 shown is a curved osteotome, it is to beunderstood that any one of several different surgical and industrialimplements can alternately be coupled to the quick disconnect assembly18, providing that they are configured with an appropriate connectingportion, or other suitable means, for coupling the desired implement tothe tool 10. Such appropriate implements include an acetabular adjuster,a surgical pin inserter, a surgical stapler, a bone chisel, anosteotome, and a gouge, for example. Further, the improved impact tool10 of the present invention may be utilized in different industrialapplications wherever an impact force is desired, such as the severaldifferent impact forces associated with construction, for instance.

The impact tool 10 can be configured into several different dimensions,along with the components of the tool 10 that produce the impact force.Thus, the tool 10 37 can be dimensioned for delivering substantiallylarge impacts of sufficient force to various fasteners, such as nails orother similar fasteners, to drive the fastener into relatively hardsurfaces comprising wood, sheetrock or drywall, or metal alloy surfacesamong others, or a somewhat slight impact force for driving smallfasteners into relatively soft surfaces. Further, the calibrating means13 is provided to enable various dimensioned tools 10 to deliver asubstantially wide range of impact forces.

An aperture 90 is disposed through the chuck 21, diametrically opposedto the opening 78 and has the push-button 92 housed therein. Thepush-button 92 is configured with an orifice 94 to engage the connectingportion 80 of the implement 42, to releasably couple the implement 42 tothe tool 10 of the present invention. A small bias spring 96 is securedin the aperture 90 for biasing the push-button 92 outwardly. In use, thepush-button 92 is depressed to compress the bias spring 96, for aligningthe orifice 94 in the button 92 with the opening 78 in the chuck 18, toallow the connecting portion 80 to pass into the opening 78 and throughthe orifice 94. Alternatively, as discussed above, the chamfered edges93 of the end 91 of the connecting portion 80 cause the end 91 toself-align in the aperture 90, as the implement 42 is being coupled tothe assembly 18, and to compress the bias spring 96 for coupling theimplement 42 to the quick disconnect assembly 18, without having todepress a push-button 92.

Once the connecting portion 80 is sufficiently disposed in the opening78, wherein the portion 80 is aligned with the orifice 94, thepush-button 92 is released by the user or self-releases once theposterior shoulder 88 is beyond the push button 92. When the button 92is released, the spring 96 biases the button 92 outwardly for engagingthe connecting portion 80, to couple the implement 42 to the chuck 21,and thus to the quick disconnect assembly 18. Optionally, a set screw 98or other suitable means can be disposed through the chuck 21 andadjusted to abut the push-button 92, to prevent the button 92 frominadvertently disengaging the implement 42.

Referring again to FIGS. 2-4, the impact inducing assembly 41 furtherincludes an actuation mechanism, shown generally at 100 in FIG. 2,configured to releasably engage the end section 68 of the rod 66. In thepreferred embodiment, the actuation mechanism 100 comprises an actuationspring 102 secured in the depression 62 and a trigger member 104slidably retained in the hole 56 and coupled to the actuation spring102. The trigger 104 has an opening 106 disposed therethrough,perpendicular to the cavity 50 to form a bottom edge 108. The opening106 is dimensioned to allow the end section 68 of the rod 66 to extendthrough the trigger 104 and into the cavity 50. The actuation spring 102is provided to bias the trigger 104 outwardly, such that a head 110thereof normally projects outwardly from the periphery of the piston 44to contact the transition region 32 of the channel 24.

Optionally, a trigger means may be disposed through the body 12 andcoupled thereto, for actuating the actuation mechanism 100. The triggermeans may be positioned on the periphery of the body 12, between thesecond end 20 and midpoint 28, depending upon such factors as theintended application of the present invention 10. For example, a triggerbutton 101 may be positioned in ovular depression 19, for example, orother suitable locations along the body 12. The trigger button 101enables the implement 42 to deliver an impact, without the user havingto exert substantial pressure on the object, to initiate the impact.Thus, the trigger button 101 enables the tool 10 to be used inapplications where only a slight impact force is desired, such asdentistry.

Referring still to FIGS. 2-4 of the drawings, in the preferredembodiment of the present invention 10, an antirotation assembly, showngenerally at 112 (in FIG. 2), is provided to prevent the implement 42from rotating relative to the longitudinal axis L, while the rod 66travels along the second region 30 of the channel 24. The antirotationassembly 112 includes an adjustable member 114 that is threaded into thethreaded portion 36 of the second region 30. The adjustable member 114has an aperture 116 disposed therethrough configured complementary tothe end and mid sections 68, 72 of the rod 66.

Preferably, the aperture 116 disposed through the member 114 is annularwith chordal sides for allowing the end and mid sections 68, 72 to passthrough the aperture 116, and to provide a slip-fit between the midsection 72 and the adjustable member 114. A locking nut 118 may furtherbe provided to prevent the adjustable member 114 from inadvertentlymoving along the threaded portion 36 of the channel's second region 30.The antirotation assembly 112 and depression 19 coact to enable a userto determine and maintain a desired orientation of various implements 42coupled to the quick disconnect assembly 18, when the implement 42 isobscured from the user's view.

Return means are included for causing the rod's end section 68 to beengaged by the actuation mechanism 100 for returning the impact inducingassembly 41 to an initial position (as shown in FIG. 3). The returnmeans comprises a return spring 120 interposed between the adjustablemember 114 and the second end 20 of the body 12 and disposed about therod's mid section 72. A circlip 122 is retained in a groove 124 in therod 66, formed about the juncture of the mid section 72 and a basesection 126 of the rod 66. The circlip 122 and locking nut 118 cooperateto retain the return spring 120 in the second region 30.

Further, an end cap 128 is threadably coupled to the second end 20 ofthe body 12. The end cap 128 has an annular opening 130 dimensioned toslip-fit the base section 126, while retaining the circlip 122 in thebody 12. The return spring 120 presses against the nut 118 and circlip122, to bias the rod 66 toward the second end 20, causing the boss 71 tobe engaged by the actuation mechanism 100.

In use, the impact inducing assembly 41 is in an initial position,wherein the main spring 64 exerts force on the piston 44 to retain theactuation mechanism 100 in the second region 30 of the channel 24, forpreventing the impact inducing assembly 41 from causing the implement 42to deliver an impact. As pressure is applied to the implement 42 by thetool 10, such as when the implement 42 is pressed against a portion ofbone (not shown), the piston 44 is urged toward the first region 26 ofthe channel 24, thus compressing the main spring 64. The piston 44 isurged into the first region 26 until the head 110 of the trigger 104contacts the transition region 32 of the channel 24.

As the trigger's head 110 the contacts the transition region 32, thetrigger 104 is pushed into the hole 56 and compresses the actuationspring 102. The trigger 104 is pushed into the hole 56 until the bottomedge 108 thereof is flush with the inner surface 60 of the piston 44.This causes the boss 71 and flange 73 to be disengaged by the trigger'sbottom edge 108, thus releasing the end section 68 of the rod 66, toallow the end section 68 to pass into the cavity 50. The main spring 64instantaneously propels the piston 44 along the end section 68, untilthe piston's second end 52 strikes the rod's shoulder 74. The mainspring 64 then instantaneously propels the piston 44 and rod 66outwardly along the channel 24, until the implement 42 impacts thedesired object (not shown) with an impact force calibrated by thecalibrating means 13. As the rod 66 is propelled along the channel'ssecond region 30, the antirotation assembly 112 prevents the rod 66 fromrotating relative to the body's longitudinal axis L.

After the implement 42 impacts the object, the piston 44 is drawn towardthe body's first end 16 by the recoil of the main spring 64, since thespring 64 is coupled to the calibrating means 13. The return spring 120retains the base section 126 of the rod 66 proximal to the body's secondend 20, for withdrawing the end section 68 out of the cavity 50. The endsection 68 is drawn out of the cavity 50, until the boss 71 passes intothe opening 106 in the trigger 104. The actuation spring 102 biases thetrigger 104 outwardly, such that the bottom edge 108 engages the boss71. This enables the tool 10 of the present invention to cause theimplement 42 to deliver subsequent impacts to the object with an impactforce determined by the calibrating means 13.

The orientation of the components of the invented impact tool 10 thatproduce an impact can essentially be inverted so that the tool 10 can beactuated to apply an instantaneous extraction force to the desiredindustrial fastener, surgical aid, etc. The orientation of thecomponents comprising the impact inducing assembly 41, along with theorientation of the transition region 32 of the channel 24, canessentially be inverted so that invented tool 10 can be actuated toapply an instantaneous extraction force to the desired fastener,surgical aid, or other piece. Additionally, the configuration of the rod66 and piston 44, along with other desired components of the tool 10,may be modified, or other suitable means may be implemented, forsecuring the rod 66 to a desired component, such as the piston 44, ofthe impact inducing assembly 41. In the alternative embodiment, when theimpact inducing assembly 41 is actuated, the assembly 41 instantaneouslydraws the quick disconnect assembly's rod 66 into the channel 24 forapplying an instantaneous extraction force to the desired object.

Referring now to FIG. 6, a possible embodiment of the extraction version150 is shown. The user calibrates the force to be applied to the objectbeing removed by adjusting the calibration knob 158, thereby adjustingthe amount of compression preapplied to the spring 162 of the impactinducing assembly 160. One end of the spring 162 is located against theend 166 of a collar 164, and the second end of the spring 162 is locatedagainst the shoulder 168 of the calibration knob 158. The collar 164 islocated around a rod 170 having an attachment mechanism (not shown)coupled to one end by a quick disconnect assembly 186. During operation,the user engages the grasping implement, such as a vice or clamp, to theobject to be drawn from the surface, then pulls the body 172 away fromthe object, thereby priming the impact inducing assembly 160. As thebody 172 moves away from the object, the trigger 174 is urged towardsand eventually contacts the transition region 176 of the channel 152.When the trigger 174 moves through the transition region 176, theopening 178 within the trigger 174 aligns with the rod 170, therebyreleasing the collar 164. The spring 162 of the impact inducing assembly160 is released and moves the collar 164 back toward its originalposition, thereby causing the end of the collar 164 to strike the head180 of the rod 170. When the collar 164 strikes the rod 170, an impactforce is imparted which creates an instantaneous pulling force on theobject. If the object has not been fully removed, the user may move thebody 172 back towards the object to reset the impact inducing assembly160. This causes the return spring 182 to realign the trigger 174 of thecollar 164 with the depression 184 in the rod 170 and locks the collar164 and rod 170 to move together as a unit. Once impact inducingassembly 160 is reset, the user may actuate the extraction tool 150again, if desired. Once the object has been fully removed, the mainspring 162 of the impact inducing assembly 160, and the return spring182 will automatically reset the extraction tool 150 to its originalposition. Although in the embodiment shown, the springs 162, 182 operatein compression, the system may be designed with tension springs ifpreferred.

Thus, there has been described an impact tool useful for performing anumber of different surgical and industrial functions. The quickdisconnect assembly is provided for alternately quickly attaching anddetaching different desired surgical and industrial implements to thetool. The orientation of the components of the impact inducing assemblycan be inverted so that the tool is actuated to apply an instantaneousextraction force to the object. The antirotation assembly and depressioncoact to enable a user to determine and maintain a desired orientationof various implements coupled to the quick disconnect assembly, when theimplement is obscured from the user's view.

Those skilled in the art will appreciate that various adaptations andmodifications of the just-described preferred embodiments can beconfigured without departing from the scope and spirit of the invention.Therefore, it is to be understood that, within the scope of the appendedclaims, the invention may be practiced other than as specificallydescribed herein.

What is claimed is:
 1. An impact tool for use with an extractionimplement, the impact tool comprising:a body having a first end, asecond end, and an opening extending therethrough, the opening having afirst diameter at the first end, a second diameter at the second end,and a transition portion which tapers between said first and seconddiameters, a calibration knob connected with the second end of the body,a rod having a first end and a second end, the first end of the rodbeing located within the body, the second end of the rod beingconfigured to connect with the extraction implement, a head extendingaround the edge of the first end of the rod, a collar located within thebody and slidably engaging the rod between the first and second endsthereof and slidably engaging the body, a trigger extending through thecollar, an impact spring positioned between the collar and thecalibration knob, the impact spring biasing the collar towards the firstend of the body, and a return spring positioned between the head of therod and the collar, the return spring biasing the head of the rod awayfrom the collar,wherein, when the extraction implement is engaged withan object to be pulled and the body of the impact tool is pulled, thecollar is moved within the opening of the body between the first andsecond diameters, causing the trigger to move between an engagedposition and a released position, thereby releasing the collar to impactthe head of the rod, causing an extraction force.
 2. The impact tool ofclaim 1 wherein the first diameter is larger than the second diameter.3. The impact tool of claim 1 wherein the collar has a shoulder andwherein the return spring engages the shoulder of the collar.
 4. Theimpact tool of claim 1 wherein the head of the rod has a shoulder andwherein an end of the return spring is positioned against the shoulder.5. The impact tool of claim 1 wherein the calibration knob is threadablyconnected to the second end of the body.
 6. The impact tool of claim 5wherein said calibration knob has a shoulder, an end of the impactspring is positioned against the shoulder.
 7. The impact tool of claim 1wherein the head is threadably attached to the first end of the rod. 8.The impact tool of claim 1 wherein:the collar has a hole formed througha wall thereof, the hole extending through the wall of the collar,perpendicular to the opening in the collar, and into an inner surfacethereof, such that a depression is formed in the inner surface of thecollar aligned with the hole, the rod has a boss formed thereon, and thetrigger has an actuation spring secured in the depression and a triggermember slidably retained in the hole and pressing against the spring,the trigger member having a bottom surface and an opening disposedtherethrough perpendicular to the bottom surface to form a bottom edge,the opening in the trigger dimensioned to allow the rod to extendthrough the trigger and into the cavity, the actuation spring biasingthe trigger member outwardly, such that a head of the trigger normallyprojects outwardly from the periphery of the collar, wherein as thecollar is moved toward the second end of the body, the head of thetrigger contacts the transition portion of the body, as the collar movesthrough the transition portion, the trigger member compresses theactuation spring until the trigger member disengages from the boss inthe rod, allowing the collar to move, whereupon the collar is impelledby the impact spring to strike the head of the rod, creating theextraction force, and wherein, when the impact tool is released, theimpact spring and return springs reset the impact tool by moving thecollar and the rod towards the first end of the body, allowing theactuation spring to push the trigger back into the boss in the rod. 9.The impact tool of claim 1 wherein the impact spring and the returnspring are compression springs.
 10. The impact tool of claim 1 furthercomprising a quick-disconnect assembly releasably connecting thegrasping implement to the rod.
 11. The tool of claim 1 wherein theimpact tool is formed from a biocompatible material.
 12. The impact toolof claim 1 wherein the calibration knob has a multiplicity of spatiallypositioned elongated furrows in the periphery thereof.
 13. An impacttool for use with an extraction implement, the impact tool comprising:abody having a first end, a second end, and an opening extendingtherethrough, the opening having a first diameter at the first end, asecond, smaller diameter at the second end, and a transition portionwhich tapers between said first and second diameters, a calibration knobhaving a shoulder, the calibration knob being connected with the secondend of the body, a rod having a first end and a second end, the firstend of the rod being located within the body, the second end of the rodbeing configured to connect with the extraction implement, a headextending around the edge of the first end of the rod, the head having ashoulder extending around the perimeter thereof, a collar located withinthe body and slidably engaging the rod between the first and second endsthereof and slidably engaging the body, the collar having a shoulder, atrigger extending through the collar, an impact compression springpositioned between the shoulder of the collar and the shoulder of thecalibration knob, the impact spring biasing the collar towards the firstend of the body, and a return compression spring positioned between theshoulder of the head of the rod and the collar, the return springbiasing the head of the rod away from the collar,wherein, when theextraction implement is engaged with an object to be pulled and the bodyof the impact tool is pulled, the collar is moved within the opening ofthe body between the first and second diameters, causing the trigger tomove between an engaged position and a released position, therebyreleasing the collar to impact the head of the rod, causing anextraction force.
 14. The impact tool of claim 13 wherein thecalibration knob is threadably connected to the second end of the body.15. The impact tool of claim 13 wherein the head is threadably attachedto the first end of the rod.
 16. The impact tool of claim 13 wherein:thecollar has a hole formed through a wall thereof, the hole extendingthrough the wall of the collar, perpendicular to the opening in thecollar, and into an inner surface thereof, such that a depression isformed in the inner surface of the collar aligned with the hole, the rodhas a boss formed thereon, and the trigger has an actuation springsecured in the depression and a trigger member slidably retained in thehole and pressing against the spring, the trigger member having a bottomsurface and an opening disposed therethrough perpendicular to the bottomsurface to form a bottom edge, the opening in the trigger dimensioned toallow the rod to extend through the trigger and into the cavity, theactuation spring biasing the trigger member outwardly, such that a headof the trigger normally projects outwardly from the periphery of thecollar, wherein as the collar is moved toward the second end of thebody, the head of the trigger contacts the transition portion of thebody, as the collar moves through the transition portion, the triggermember compresses the actuation spring until the trigger memberdisengages from the boss in the rod, allowing the collar to move,whereupon the collar is impelled by the impact spring to strike the headof the rod, creating the extraction force, and wherein when the impacttool is released, the impact spring and return springs reset the impacttool by moving the collar and the rod towards the first end of the body,allowing the actuation spring to push the trigger back into the boss inthe rod.
 17. The impact tool of claim 13 further comprising aquick-disconnect assembly releasably connecting the grasping implementto the rod.
 18. The tool of claim 13 wherein the impact tool is formedfrom a biocompatible material.